离散光电成像系统因其不再具有平移不变特性,它的调制传递函数测试具有相当的复杂性和不稳定性。为提高光学系统调制传递函数测试的灵活性和可重复性,在基于统计光学和随机信号相关性理论的基础上,分析了离散型空间随机信号经线性光学系统成像后的物像相关性,提出了应用随机条纹靶来测定调制传递函数的方法,并给出了计算数据结果。该方法从统计意义上考虑了离散采样成像器件的采样场景相位的影响,大大提高了现场测试的灵活性和自动化程度,具有很好的应用前景。此方法同样适用于一般光学成像系统的调制传递函数测量。

The measurement of modulation transfer function (MTF) of the sampled imaging opto-electronic system is rather complex and irrepeatable for their shift-variant characteristics. Based on the theory of statistical optics and stochastic process, the correlation relationship of spatially discrete random signal pattern and its correspoding image through a linear optical imaging system are analyzed. A method using random bar pattern for modulation transfer function measurement is proposed, and the emulational experimental result is demonstrated. The random bar pattern test method reduces the effect of sample-scene phasing of sampled imaging device in statistical sense. This method is also adapted to the MTF measurement of commonly shift-invariant optical system and is expected to greatly improve the flexibilities and automation degree of MTF testing.